Earth Sciences 2281A/B Lecture Notes - Lecture 9: Diel Vertical Migration, Porosity, Capillary Fringe

• School: Western University
• Department: Earth Sciences
• Course: Earth Sciences 2281A/B
• Professor: Robert Schincariol

Document Summary

Population drinking groundwater canada ~25%, e. g. kitchener-waterloo, winnipeg, Water table level at which water would rise in a cased hole, pressure=atmospheric. Capillary fringe zone above water table where groundwater is lifted against gravity by capillary or surface tension forces, in tiny, threadlike passages between grains of sediment. Zones, pressure, and saturation: unsaturated zone: p < atm, sat <100, capillary fringe: p < atm, sat = 100, water table: p = atm, sat = 100, saturated zone: p > atm, sat = 100% Porosity = volume of voids/ total volume. Clay = 0. 5, sand = 0. 25, limestone & sandstone = 0. 5-0. 15, granite = Permeability, k = ability to transmit water based on medium properties. Hydraulic conductivity, k = ability to transmit water based on fluid and medium properties, varies over 13 orders of magnitude. Igneous rocks 10-10 cm/s, sandstone 10-4-10-8 cm/s, sand 10-3cm/s.